This invention relates to a bioabsorbable copolymer and, more particularly, to a bioabsorbable copolymer obtained by polymerizing a major amount of .epsilon.-caprolactone and a minor amount of at least one other copolymerizable monomer in the presence of an initiator possessing at least two carboxylic acid groups.
U.S. Pat. No. 2,362,511 discloses a polyglycolide resin derived from glycolide and from about 20 to about 55 weight percent of a carboxylic acid such as lactic acid, tartaric acid, malic acid, citric acid, etc.
U.S. Pat. No. 3,169,945 discloses a homopolymer of .epsilon.-caprolactone obtained by polymerizing .epsilon.-caprolactone in the presence of a carboxylic acid initiator such as citric acid, aconitic acid, mellitic acid, pyromellitic acid, etc.
U.S. Pat. No. 3,942,532 discloses a surgical suture coating composition comprising a polyester derived from the esterification of a low molecular weight glycol and a dimeric acid such as succinic acid, glutaric acid, adipic acid, etc.
U.S. Pat. No. 4,624,256 discloses a bioabsorbable copolymer derived from at least 90 weight percent of .epsilon.-caprolactone and up to 10 weight percent of a carboxylic acid such as glycolic acid, lactic acid, malic acid, succinic acid, etc.
U.S. Pat. No. 4,643,191 discloses a copolymer obtained by: (1) the polymerization of p-dioxanone in the presence of a carboxylic acid initiator such as glycolic acid, lactic acid, etc., to form a mixture of p-dioxanone monomer and homopolymer and (2) subsequent polymerization of (1) with lactide to form the copolymer.
U.S. Pat. No. 5,076,807 discloses a bioabsorbable copolymer derived from polymerizing p-dioxanone and glycolide in the presence of a carboxylic acid initiator, e.g., glycolic acid or lactic acid.
Copolymers derived from .epsilon.-caprolactone and at least one other monomer such as lactide, glycolide, glycolic acid, p-dioxanone and trimethylene carbonate are disclosed in U.S. Patent Nos. 4,605,730, 4,624,256, 4,700,704, 4,788,979, 4,791,929, 4,994,074, 5,076,807, 5,080,665, 5,085,629 and 5,100,433.